Touch display and manufacturing method thereof

ABSTRACT

A touch display comprises a color filter substrate, an array substrate opposite to the color filter via a plurality of spacers and a voltage detection circuit. The color filter substrate comprises an upper substrate and a common electrode formed on the upper substrate, and the array substrate comprises a lower substrate and a gate line, a data line and a pixel electrode formed on the lower substrate. The plurality of spacers comprise a first spacer formed between the gate line and the common electrode and a second spacer formed between the data line and the common electrode , which are capable of electrically connecting the common electrode with the gate line and the data line respectively under an external pressure more than a threshold value. The voltage detection circuit is connected with the gate line and the data line so as to detect whether the voltage on the gate line and the voltage on the data line become equal to the voltage of the common electrode.

BACKGROUND

Embodiments of the present invention relate to a touch display and amanufacturing method thereof.

In the recent ten years, liquid crystal displays (LCDs) are developedrapidly and achieve a great improvement on screen size, display qualityand the like. Furthermore, the LCDs have the advantage of small volume,low energy consumption, low radiation, and etc., and thus prevail in theflat panel display market.

In a liquid crystal display, a touch display is an important deviceintegrating the function of an input terminal and an output terminal. Assmall and light handheld devices such as the Iphone (trademark)manufactured by Apple Inc. was put into market, the demand for the touchdisplay is increasing. A touch display can be typically formed byimposing a touch screen on a display screen, that is, two screens aremanufactured for forming the touch display, and thus the manufacturecost is increased.

SUMMARY

A touch display comprises a color filter substrate, an array substrateopposite to the color filter via a plurality of spacers and a voltagedetection circuit. The color filter substrate comprises an uppersubstrate and a common electrode formed on the upper substrate, and thearray substrate comprises a lower substrate and a gate line, a data lineand a pixel electrode formed on the lower substrate. The plurality ofspacers comprise a first spacer formed between the gate line and thecommon electrode and a second spacer formed between the data line andthe common electrode , which are capable of electrically connecting thecommon electrode with the gate line and the data line respectively underan external pressure more than a threshold value. The voltage detectioncircuit is connected with the gate line and the data line so as todetect whether the voltage on the gate line and the voltage on the dataline become equal to the voltage of the common electrode.

A method of manufacturing a touch display is provided in anotherembodiment of the invention. The method comprises: providing a colorfilter substrate, the color filter substrate comprising an uppersubstrate and a common electrode formed on the upper substrate;providing an array substrate, the array substrate comprising a lowersubstrate, and a gate line, a data line and a pixel electrode formed onthe lower substrate, wherein a plurality of spacers are formed on thearray substrate and comprise a first spacer connected with the gate lineand a second spacer connected with the data line; and assembling thecolor substrate and the array substrate to form the touch display,wherein the first and second spacers abut against the common electrodeon the color filter substrate and are capable of electrically connectingthe common electrode with the gate line and the data line respectivelyunder an external pressure more than a threshold value.

Further another embodiment of the invention also provides a method ofmanufacturing a touch display and may comprise the following steps:providing a color filter substrate, the color filter substratecomprising an upper substrate, a common electrode formed on the uppersubstrate, and a plurality of spacers formed on the common electrode andconnected with the common electrode; providing an array substrate, thearray substrate comprising a lower substrate, and a gate line, a dataline and a pixel electrode formed on the lower substrate; and assemblingthe color substrate and the array substrate to form the touch display,wherein the plurality of spacers comprise a first spacer abuttingagainst the gate line on the array substrate and a second spacerabutting against the data line on the array substrate , which arecapable of electrically connecting the common electrode with the gateline and the data line respectively under an external pressure more thana threshold value.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from the following detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinafter and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention and wherein:

FIG. 1 is a top view showing an array substrate in a first embodiment ofa touch display according to the invention;

FIG. 2 is a sectional view showing a spacer formed at a position on agate line in the first embodiment of the touch display according to theinvention;

FIG. 3 is a sectional view showing a spacer formed at a position on adata line in the first embodiment of the touch display according to theinvention;

FIG. 4 is a schematic view showing the spacer of FIG. 2 under anexternal pressure; and

FIG. 5 is a schematic view showing the spacer of FIG. 3 under anexternal pressure.

DESCRIPTION OF THE EMBODIMENTS

A touch display and a manufacturing method thereof, which are capable ofintegrating a touch screen and a display screen into a single screen sothat the touch display can become thinner, are provided in theembodiments of the invention.

Hereinafter, the embodiments of the present invention will be describedin detail with reference to the accompanying drawings.

First Embodiment of The Touch Display

FIG. 1 is a top view showing an array substrate in a first embodiment ofa touch display according to the invention; FIG. 2 is a sectional viewshowing a spacer formed at a position on a gate line in the firstembodiment of the touch display according to the invention; and FIG. 3is a sectional view showing a spacer formed at a position on a data linein the first embodiment of the touch display according to the invention.

As shown in FIGS. 1-3, the touch display 100 provided in the firstembodiment comprises a filter color substrate and an array substrateopposite to the color filter substrate. The color filter substratecomprises an upper substrate 11 and a common electrode 12 formed on theupper substrate 11, and the array substrate comprises a lower substrate21 and a gate line 22, a data line 23 and a pixel electrode 26 formed onthe lower substrate 21. A plurality of spacers 15, which are capable ofelectrically connecting the common electrode 12 with the gate line 22and the data line 23 under an external pressure more than the thresholdvalue are further formed on the common electrode 12. For example, thespacer 15 corresponding to the gate line 22 can be called as the firstspacer, while the spacer 15 corresponding to the data line 23 can becalled as the second spacer. The touch display 100 further comprises avoltage detection circuit (not shown). The voltage detection circuit isconnected with the gate line 22 and the data line 23 for detectingwhether the voltage on the gate line 22 and the voltage on the data line23 is equal to the voltage of the common electrode 12. Preferably, thevoltage detection circuit is provided on the array substrate; on theother hand, the voltage detection circuit may be provided separately oron the color filter substrate.

In the touch display 100 in the this embodiment, the plurality ofspacers 15 are provided on the common electrode 12 formed on the colorfilter substrate, and at the same time, each of the plurality of spacers15 abuts against the gate line 22 or the data line 23 formed on thearray substrate. When one spacer 15 is under an external pressure morethan the threshold value, the common electrode 12 can be electricallyconnected with the corresponding gate line 22 or data line 23.Accordingly, whether the voltage on the gate line 22 or the data line 23at the touch point is equal to the voltage of the common electrode canbe detected by the voltage detection circuit, and thus the position ofthe touch point can be determined. In this way, a single touch displaycan have the functions of both of the touch screen and the displayscreen, and thus the manufacture process can be simplified and themanufacture cost can be reduced. In addition, in the touch display 100,the problem that the touched is not the seen due to the misalignmentbetween the screens and refraction between the display screen and thetouch screen can be avoided, and thus the color stability of the colorfilter substrate can be improved and the manufacture accuracy can beincreased. Therefore, the product quality and the manufacture efficiencyof the thin film transistor liquid crystal display (TFT-LCD) employingthe touch display with the above-described structure can be increased,and thus the manufacture cost can be further reduced.

As shown in FIG. 2 and FIG. 3, a black matrix 13 is formed on the commonelectrode 12, and a plurality of black matrix via holes 131 are formedin the black matrix 13. The spacers 15 are connected with the commonelectrode 12 through the black matrix via holes 131. In order to ensurethe light transmission of in the pixel region, for example, the spacers15 may be formed at the positions corresponding to the black matrix 13.The common electrode 12 may be directly formed on the upper substrate 11on which a color filter unit 14 has been formed.

Second Embodiment of The Touch Display

The second embodiment is different from the first embodiment in that:the black matrix 13 is formed on the upper substrate 11 on which thecolor filter unit 14 has been formed, the common electrode 12 is formedon the black matrix 13 and the spacers 15 are directly connected withthe common electrode 12. In order to ensure the light transmission of inthe pixel region, the spacers 15 are provided at the positionscorresponding to the black matrix 13.

Third Embodiment of The Touch Display

The third embodiment is based on the combination of the first and secondembodiments. FIG. 2 is a sectional view taken along the line A-A in FIG.1 and FIG. 3 is a sectional view taken along the line B-B in FIG. 1. Asshown in FIG. 2 and FIG. 3, in the third embodiment, a passivation layer24 is further formed on the lower substrate 21, passivation layer viaholes 25 are formed at positions corresponding to the spacers 15, andeach of the spacers 15 abuts against the gate line 22 or the data line23 through the respective passivation layer via hole 25. Since thepassivation layer 24 is formed on the gate line 22 and the data line 23,it is necessary to form the passivation layer via holes 25 so that thespacers 15 abut against the gate line 22 and the data line 23. Inaddition, as shown, the passivation layer via hole 25 on the gate line22 necessarily penetrates both of the passivation layer 24 and a gateinsulating layer 28, and the passivation layer via hole 25 on the dataline penetrates the passivation layer 24 only.

Furthermore, a conductive protection layer 27 is formed at each of thepassivation layer via holes 25. The conductive protection layer 27ensures that the spacers 15 are positioned in the passivation layer viaholes 25 irrespective of whether the spacers 15 are deformed underpressing or not. In addition, the conductive protection layer 27 canavoid accidental electrical conduction.

Furthermore, the conductive protection layer 17 is formed in the samelayer as the pixel electrode 26. For example, the conductive protectionlayer 17 may be formed by transparent material such as indium tin oxide(ITO) or indium zinc oxide (IZO).

In the above first, second and third embodiments, the spacers 15 arecolumnar spacers, and the spacers 15 can be formed by a mixture materialof resin or rubber with conductive particles 151. Preferably, epoxyresin, polyurethane resin or elastic plastic resin can be used for theresin. The resin or the rubber has an elastic netlike structure so thatthe conductive particles (e.g., metal particles or carbon particles) 151can be mixed therein. Under an external pressure, a favorable contactcan be obtained among the conductive particles. When the externalpressure does not exist or is smaller than the threshold value, most ofthe dispersed conductive particles 151 are still separated and insulatedfrom each other. FIG. 4 is a schematic view showing the spacer of FIG. 2under an external pressure; and FIG. 5 is a schematic view showing thespacer of FIG. 3 under an external pressure. As shown in FIG. 4 and FIG.5, under the external pressure larger than the threshold value, most ofthe conductive particles 151 at the position subject to the externalpressure contact with each other, in which case a conduction path can beestablished in the vertical direction and both ends of the spacer 15 areelectrically connected; after the external pressure is released, theresin or the rubber recovers as it is originally, and thus theconductive particles 151 are separated and insulated from each otheragain. Here, the spacers 15 under pressing function like an anisotropyconductive material.

In addition, as shown in FIG. 2 and FIG. 3, alignment layers 29 areapplied on the upper substrate 11 and the lower substrate 21,respectively. One alignment layer 29 is formed on the entirety of theconductive protection layer 27. Since the spacer 15 containing metalparticles has a relatively high hardness, the spacers 15 can penetratethe alignment layer 29 and abut on the conductive protection layer 27 soas to be ready to constitute an electrical connection when the colorfilter substrate and the array substrate are assembled together. Inorder that the spacers 15 can reliably abut against the conductiveprotection layer 27, the alignment layer 29 at the passivation layer viaholes 25 can be etched away, and thus a better electrical connection canbe obtained.

On the other hand, in the embodiments, the spacers 15 can also be formedon the array substrate at positions on the gate line and data line.After the color filter substrate and the array substrate are assembledtogether, the spacers 15 formed on the array substrate can abut againstthe common electrode formed on the color filter substrate. Furthermore,a conductive protection layer can be formed at the positionscorresponding to the spacers 15. Under an external pressure more thanthe threshold value, the spacers can become conductive in the verticaldirection for electrically connecting the gate line and data line on thearray substrate and common electrode on the color filter substrate.

Hereinafter, the operation mechanism of the touch display in theembodiments will be explained.

When a point on the touch display is touched and the external pressureat the touch point is larger than the threshold value, the gate line atthe touch point, for example, is electrically connected with the commonelectrode on the color filter substrate by the conductive particlescontained in the corresponding spacer, and at the same time, the dataline at the touch point, for example, is also electrically connectedwith the common electrode on the color filter substrate by theconductive particles contained in another corresponding spacer. Thus, atthe touch point, both the voltage on the gate line and the voltage onthe data line become equal to the common voltage. Then, the voltagedetection circuit connecting with the gate line and the data linefeedbacks the serial numbers of the gate line and the data line with thevoltage equal to the common voltage to a controller, and thus thecoordinates of the touch point can be determined in the controller.

At the same time, one vertical line and one horizontal line may beformed at the touch point, and thus the user can judge whether thecorrect position is touched by the cross point of these two lines.

The mechanism of forming the vertical and horizontal lines is explainedas follows. When the common electrode on the color filter substrate iselectrically connected with the gate line at the touch point, thevoltage on the gate line becomes equal to the common voltage, and thusthe thin film transistors (TFTs) of the pixels corresponding to the gateline are all turned on so that one lateral bright line appearscorresponding to the gate line. Because the area of the touch point bythe object (such as a finger, a pen and the like) touching the screen ismuch larger than that of a sub-pixel, the width of bright line issubstantially equal to the diameter of the touch point. Similarly, whenthe common electrode on the color filter substrate is electricallyconnected with the data line at the touch point, the voltage on the dataline becomes equal to the common voltage, and thus the same voltage(equal to the common voltage) is applied on the pixels corresponding tothe data line when the gate lines are scanned line by line so that oneuniform and vertical bright line appears. The area of the touch point ofthe object (such as a finger, a pen and the like) touching the screen ismuch larger than that of a sub-pixel, the pixels of three primary colorsof RGB (Red, Green, and Blue) are uniformly formed in the direction of agate line, and the pixels have the same voltage. Therefore, at the touchpoint, one white line formed by the three primary colors of RGB extendsin the direction of the data line, and the width of white line issubstantially equal to the diameter of the touch point.

A method of manufacturing a touch display is also provided in anembodiment of the invention. The method may comprise the followingsteps: forming a color filter substrate with a plurality of spacerswhich are conductive under an external pressure more than a thresholdvalue and connected with a common electrode; forming an array substratecomprising a gate line and a data line; assembling the color substrateand the array substrate to form the touch display. The spacers abutagainst the gate line and the data line on the array substrate andcapable of electrically connecting the common electrode with thecorresponding gate line and the corresponding data line under anexternal pressure more than the threshold value. The touch display mayfurther comprise a voltage detection circuit. The voltage detectioncircuit is connected with the gate line and the data line so as todetect whether the voltage on the gate line and the voltage on the dataline is equal to the voltage of the common electrode.

Hereinafter, embodiments of the manufacturing method of the touchdisplay will be described hereinafter in detail.

First Embodiment of The Manufacturing Method of the Touch Display

The touch display is formed by assembling a color filter substrate andan array substrate. The step of forming the color filter substrate withthe plurality of spacers which are conductive under an external pressureand connected with the common electrode comprises the following steps.

Step 1011 of forming a color filter unit on an upper substrate.

Step 1012 of forming the common electrode on the upper substrate withthe color filter unit;

Step 1013 of forming a black matrix with a plurality of black matrix viaholes on the upper substrate with the common electrode; and

Step 1014 of forming the plurality of spacers which are conductive underpressing on the upper substrate with the black matrix, the plurality ofspacers being connected with the common electrode through the blackmatrix via holes.

Forming the array substrate by patterning process may comprise thefollowing steps.

Step 1021 of depositing a gate metal film on a lower substrate andforming a gate line and a gate electrode by patterning.

Step 1022 of depositing a gate insulating film, an amorphous siliconfilm (a semiconductor film) and a doped amorphous silicon film (a dopedsemiconductor film) in this order on the lower substrate and forming anactive layer on the gate electrode by patterning.

Step 1023 of depositing a source/drain metal film on the lower substrateand forming a data line, a source electrode and a drain electrode bypatterning, wherein a thin film transistor (TFT) channel is formedbetween the source electrode and the drain electrode.

Step 1024 of depositing a passivation layer on the lower substrate andforming a plurality of passivation layer via holes at positionscorresponding to the spacers so that the spacers abut against the gateline and the data line through the passivation layer via holes.

Step 1025 of depositing a transparent conductive film on the lowersubstrate and forming the pixel electrode and a conductive protectionlayer by patterning, wherein the conductive protection layer is remainedat the passivation layer via holes.

The active layer comprises the stack of the patterned amorphous siliconfilm and the patterned doped amorphous silicon film and shaped like anisland.

In the above embodiment, a five-patterning (five-mask) process is usedas an example of the manufacturing method. The patterning process usedhere may comprise the processes of applying photoresist, masking,exposing and developing the photoresist, etching with a photoresistpattern, lifting-off the remaining photoresist and the like.

In practical, a four-patterning process or even a three-patterningprocess are also applicable here also. That is, the gate line, the dataline and the thin film transistor on an array substrate may be formed byvarious ways. For example, as for a four-patterning processes, the aboveStep 1022 and Step 1023 can be combined into a single step andaccomplished in one patterning process. Specifically, the gateinsulating layer, the amorphous silicon film, the doped amorphoussilicon film and the source/drain metal film are deposited on the lowersubstrate sequentially in this order, the active layer, the data line,the source electrode and the drain electrode are formed by patterning,and the TFT channel is formed between the source electrode and the drainelectrode.

With the method of manufacturing the touch display in this embodiment ofthe invention, the plurality of spacers are provided on the commonelectrode formed on the color filter substrate, the plurality of spacersare capable of electrically connecting the common electrode with thegate line and the data line under an external pressure more than thethreshold value, and thus a single touch display can have the functionsof both of a touch screen and a display screen. Therefore, themanufacture process can be simplified and the manufacture cost can bereduced. In addition, with the method of manufacturing the touch displayin this embodiment of the invention, the problem that the touched is notthe seen due to the misalignment and refraction between the displayscreen and the touch screen can be avoided, and thus the color stabilityof the color filter substrate can be improved and the manufactureaccuracy can be increased. Therefore, the product quality and themanufacture efficiency of the TFT-LCD employing the touch display withthe above-described structure can be increased, and thus the manufacturecost can be further reduced.

Second Embodiment of The Manufacturing Method of the Touch Display

The second embodiment of the manufacturing method of the touch displayis different from the first embodiment in that: the step of forming thecolor filter substrate with the plurality of spacers which are connectedwith the common electrode may comprise the following steps.

Step 1011′ of forming a black matrix on an upper substrate;

Step 1012′ of forming a color filter unit on the upper substrate withthe black matrix;

Step 1013′ of forming the common electrode on the upper substrate withthe color filter unit; and

Step 1014′ of forming the plurality of spacers which are conductiveunder an external pressure on the upper substrate with the commonelectrode, wherein the plurality of spacers are connected with thecommon electrode.

The step of forming the array substrate can be the same as that in thefirst embodiment, and the detailed description thereof is omitted herefor simplicity.

With the method of manufacturing the touch display in this embodiment ofthe invention, the plurality of spacers are provided on the commonelectrode formed on the color filter substrate, the plurality of spacersare capable of electrically connecting the common electrode with thegate line and the data line under an external pressure more than thethreshold value, and thus a single touch display can have the functionsof both of the touch screen and the display screen. Therefore, themanufacture process can be simplified and the manufacture cost can bereduced. In addition, with the method of manufacturing the touch displayin this embodiment of the invention, the problem that the touched is notthe seen due to the misalignment and refraction between the displayscreen and the touch screen can be avoided, and thus the color stabilityof the color filter substrate can be improved and the manufactureaccuracy can be increased. Therefore, the product quality and themanufacture efficiency of the TFT-LCD employing the touch display withthe above-described structure can be increased, and thus the manufacturecost can be further reduced.

Another embodiment of the invention provides a method of manufacturing atouch display and may comprise the following steps: providing a colorfilter substrate, the color filter substrate comprising an uppersubstrate and a common electrode formed on the upper substrate;providing an array substrate, the array substrate comprising a lowersubstrate, and a gate line, a data line and a pixel electrode formed onthe lower substrate, wherein a plurality of spacers are formed on thearray substrate and comprise a first spacer connected with the gate lineand a second spacer connected with the data line; and assembling thecolor substrate and the array substrate to form the touch display,wherein the first and second spacers abut against the common electrodeon the color filter substrate and are capable of electrically connectingthe common electrode with the gate line and the data line respectivelyunder an external pressure more than a threshold value.

It should be appreciated that the embodiments described above areintended to illustrate but not limit the present invention. Although thepresent invention has been described in detail herein with reference tothe preferred embodiments, it should be understood by those skilled inthe art that the present invention can be modified and some of thetechnical features can be equivalently substituted without departingfrom the spirit and scope of the present invention.

What is claimed is:
 1. A method of manufacturing a touch display,comprising: providing a color filter substrate, the color filtersubstrate comprising an upper substrate and a common electrode formed onthe upper substrate; providing an array substrate, the array substratecomprising a lower substrate, and a gate line, a data line and a pixelelectrode formed on the lower substrate, wherein a plurality of spacersare formed on the array substrate and comprise a first spacer connectedwith the gate line and a second spacer connected with the data line; andassembling the color substrate and the array substrate to form the touchdisplay, wherein the first and second spacers abut against the commonelectrode on the color filter substrate and are capable of electricallyconnecting the common electrode with the gate line and the data linerespectively under an external pressure more than a threshold value. 2.A method of manufacturing a touch display, comprising: providing a colorfilter substrate, the color filter substrate comprising an uppersubstrate, a common electrode formed on the upper substrate, and aplurality of spacers formed on the common electrode and connected withthe common electrode; providing an array substrate, the array substratecomprising a lower substrate, and a gate line, a data line and a pixelelectrode formed on the lower substrate; and assembling the colorsubstrate and the array substrate to form the touch display, wherein theplurality of spacers comprise a first spacer abutting against the gateline on the array substrate and a second spacer abutting against thedata line on the array substrate, which are capable of electricallyconnecting the common electrode with the gate line and the data linerespectively under an external pressure more than a threshold value. 3.The method of manufacturing the touch display according to claim 2,wherein providing the color filter substrate comprises the followingsteps: forming a color filter unit on the upper substrate; forming thecommon electrode on the upper substrate with the color filter unit;forming a black matrix with a plurality of black matrix via holes on theupper substrate with the common electrode; and forming the plurality ofspacers on the upper substrate with the black matrix, wherein thespacers are connected with the common electrode through the black matrixvia holes.
 4. The method of manufacturing the touch display according toclaim 2, wherein the step of providing the color filter substratecomprises the following steps: forming a black matrix on the uppersubstrate; forming a color filter unit on the upper substrate with theblack matrix; forming the common electrode on the upper substrate withthe color filter unit; and forming the plurality of spacers on the uppersubstrate with the common electrode.
 5. The method of manufacturing thetouch display according to claim 2, wherein providing the arraysubstrate comprises the following steps: forming the gate line, the dataline and a thin film transistor on the lower substrate; depositing apassivation layer on the lower substrate, and forming a plurality ofpassivation layer via holes in the passivation layer at positionscorresponding to the spacers by patterning, so that the spacers abutagainst the gate line and the data line through the passivation layervia holes; and depositing a transparent conductive film on the lowersubstrate, and forming the pixel electrode and a conductive protectionlayer by patterning, the conductive protection layer being remained atthe passivation layer via holes.
 6. The method of manufacturing thetouch display according to claim 2, further comprising: providing avoltage detection circuit, wherein the voltage detection circuit isconnected with the gate line and the data line so as to detect whetherthe voltage on the gate line and the voltage on the data line becomeequal to the voltage of the common electrode.
 7. The method ofmanufacturing the touch display according to claim 6, wherein thevoltage detection circuit is provided on the array substrate.